Практическое руководство. Настройка полей флажков и значков для объекта ContextMenuStrip

Элемент управления ContextMenuStrip можно настраивать, устанавливая свойства ShowImageMargin и ShowCheckMargin в различных сочетаниях.

Пример

В примере кода ниже показано, как установить и настроить поля флажков и значков для элемента управления ContextMenuStrip.

using System;
using System.Collections.Generic;
using System.Windows.Forms;
using System.Drawing;

// This code example demonstrates how to set the check
// and image margins for a ToolStripMenuItem.
class Form5 : Form
{
    public Form5()
    {
        // Size the form to show three wide menu items.
        this.Width = 500;
        this.Text = "ToolStripContextMenuStrip: Image and Check Margins";

        // Create a new MenuStrip control.
        MenuStrip ms = new MenuStrip();

        // Create the ToolStripMenuItems for the MenuStrip control.
        ToolStripMenuItem bothMargins = new ToolStripMenuItem("BothMargins");
        ToolStripMenuItem imageMarginOnly = new ToolStripMenuItem("ImageMargin");
        ToolStripMenuItem checkMarginOnly = new ToolStripMenuItem("CheckMargin");
        ToolStripMenuItem noMargins = new ToolStripMenuItem("NoMargins");

        // Customize the DropDowns menus.
        // This ToolStripMenuItem has an image margin 
        // and a check margin.
        bothMargins.DropDown = CreateCheckImageContextMenuStrip();
        ((ContextMenuStrip)bothMargins.DropDown).ShowImageMargin = true;
        ((ContextMenuStrip)bothMargins.DropDown).ShowCheckMargin = true;

        // This ToolStripMenuItem has only an image margin.
        imageMarginOnly.DropDown = CreateCheckImageContextMenuStrip();
        ((ContextMenuStrip)imageMarginOnly.DropDown).ShowImageMargin = true;
        ((ContextMenuStrip)imageMarginOnly.DropDown).ShowCheckMargin = false;

        // This ToolStripMenuItem has only a check margin.
        checkMarginOnly.DropDown = CreateCheckImageContextMenuStrip();
        ((ContextMenuStrip)checkMarginOnly.DropDown).ShowImageMargin = false;
        ((ContextMenuStrip)checkMarginOnly.DropDown).ShowCheckMargin = true;

        // This ToolStripMenuItem has no image and no check margin.
        noMargins.DropDown = CreateCheckImageContextMenuStrip();
        ((ContextMenuStrip)noMargins.DropDown).ShowImageMargin = false;
        ((ContextMenuStrip)noMargins.DropDown).ShowCheckMargin = false;

        // Populate the MenuStrip control with the ToolStripMenuItems.
        ms.Items.Add(bothMargins);
        ms.Items.Add(imageMarginOnly);
        ms.Items.Add(checkMarginOnly);
        ms.Items.Add(noMargins);

        // Dock the MenuStrip control to the top of the form.
        ms.Dock = DockStyle.Top;

        // Add the MenuStrip control to the controls collection last.
        // This is important for correct placement in the z-order.
        this.Controls.Add(ms);
    }

    // This utility method creates a Bitmap for use in 
    // a ToolStripMenuItem's image margin.
    internal Bitmap CreateSampleBitmap()
    {
        // The Bitmap is a smiley face.
        Bitmap sampleBitmap = new Bitmap(32, 32);
        Graphics g = Graphics.FromImage(sampleBitmap);

        using (Pen p = new Pen(ProfessionalColors.ButtonPressedBorder))
        {
            // Set the Pen width.
            p.Width = 4;

            // Set up the mouth geometry.
            Point[] curvePoints = new Point[]{
                new Point(4,14), 
                new Point(16,24), 
                new Point(28,14)};

            // Draw the mouth.
            g.DrawCurve(p, curvePoints);

            // Draw the eyes.
            g.DrawEllipse(p, new Rectangle(new Point(7, 4), new Size(3, 3)));
            g.DrawEllipse(p, new Rectangle(new Point(22, 4), new Size(3, 3)));
        }

        return sampleBitmap;
    }

    // This utility method creates a ContextMenuStrip control
    // that has four ToolStripMenuItems showing the four 
    // possible combinations of image and check margins.
    internal ContextMenuStrip CreateCheckImageContextMenuStrip()
    {
        // Create a new ContextMenuStrip control.
        ContextMenuStrip checkImageContextMenuStrip = new ContextMenuStrip();

        // Create a ToolStripMenuItem with a
        // check margin and an image margin.
        ToolStripMenuItem yesCheckYesImage = 
            new ToolStripMenuItem("Check, Image");
        yesCheckYesImage.Checked = true;
        yesCheckYesImage.Image = CreateSampleBitmap();

        // Create a ToolStripMenuItem with no
        // check margin and with an image margin.
        ToolStripMenuItem noCheckYesImage = 
            new ToolStripMenuItem("No Check, Image");
        noCheckYesImage.Checked = false;
        noCheckYesImage.Image = CreateSampleBitmap();

        // Create a ToolStripMenuItem with a
        // check margin and without an image margin.
        ToolStripMenuItem yesCheckNoImage = 
            new ToolStripMenuItem("Check, No Image");
        yesCheckNoImage.Checked = true;

        // Create a ToolStripMenuItem with no
        // check margin and no image margin.
        ToolStripMenuItem noCheckNoImage = 
            new ToolStripMenuItem("No Check, No Image");
        noCheckNoImage.Checked = false;

        // Add the ToolStripMenuItems to the ContextMenuStrip control.
        checkImageContextMenuStrip.Items.Add(yesCheckYesImage);
        checkImageContextMenuStrip.Items.Add(noCheckYesImage);
        checkImageContextMenuStrip.Items.Add(yesCheckNoImage);
        checkImageContextMenuStrip.Items.Add(noCheckNoImage);

        return checkImageContextMenuStrip;
    }
}

Компиляция кода

Для этого примера требуются:

  • ссылки на сборки System.Design, System.Drawing и System.Windows.Forms.

Сведения о выполнении сборки этого примера из командной строки для Visual Basic или Visual C#, см. в разделе построение из командной строки или командной строки создания с помощью csc.exe. Можно также сборке этого примера в Visual Studio путем вставки кода в новый проект.

См. также